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  #31  
Old 04-24-2017, 09:48 AM
Truckjohn Truckjohn is offline
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I havent pore filled per-se, but I have used a lot of epoxy and CA on my guitars and I have had some pretty impressive catastrophes.

Here are a few:
CA wicking deep into end grain/wavy grain/figure and leaving weird blotches in places.
CA kicking over too hard and foaming up.... Turns into ugly white/yellowish porous hard rock foam. It seems like it was worse on deeper fills.
CA soaking into a ding I was drop filling and leaving a dark, ugly stain under the finish.
CA joints turning dark surrounded by very light wood - ugly...
CA is often harder to sand than the surrounding wood...

Epoxy wicking deep into end/wavy grain/figure leaving weird blotches.
Epoxy not kicking over and staying gooey (a hair dryer is your friend)
Epoxy kicking over too fast and gelling in the middle of the work
Epoxy peeling back off the wood and out of the ding when sanding a filled ding..
Many epoxies yellow over time - which isnt good on a water clear finish.. But doesn't seem to matter on an amber/yellow/darker finish like Varnish.

My experience is that epoxy is much less likely to leave blotches and dark spots than CA. It also is pretty transparent under your finish - and thats nice when filling in a chip. CA can leave a dark pock mark when you fill a chip...

Thicker epoxies like the cheap hardware store stuff tends to lay on the wood where the good thin stuff for boat building like West soaks in more. CA goes way down into the wood.. That makes clean up of the epoxy drips more likely to succeed vs CA...

When I do get around to pore filling - I am probably going to try either epoxy or a commercial pore filler product first. But I could see that there is significant learning curve either way...
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  #32  
Old 04-24-2017, 09:19 PM
Mr Fingers Mr Fingers is offline
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I don't understand the point of working with physically vile, expensive CA unless you really want to change the property of the wood itself into something more brittle. Epoxy has long been regarded as a tone killer and a heavy substance, so I don't see the point of using it even if you like how it behaves. Though I hate the stuff and dislike the process, standard pore-filler performs best for me now that I have developed a touch for it. It doesn't weigh down the wood, and color control is good. I sometimes use shellac to seal and fill, and unless the wood is really open pore, it works. Frankly, I think most of us gravitate towards whatever process we can control best.
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  #33  
Old 04-24-2017, 09:43 PM
phavriluk phavriluk is offline
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I think there is a direct relationship between how quickly something needs to be managed and the skill needed to make it work.

Now, CA works mighty quickly. To achieve any kind of reasonable success with it, I think the person using it needs to have a whole lot of experience with it in similar situations to get good results. It ain't hard to create a near-irreversible mess when CA is involved. I think CA is particularly hard to control. For anybody who's seen the Disney cartoon 'Sorcerer's Apprentice', I think that applies to CA.
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  #34  
Old 04-24-2017, 11:05 PM
tadol tadol is offline
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Someone in the NCAL group was doing a full finish with nothing but CA - seemed to have worked out the technique, and while the instrument was pretty new, seemed to look good. I'll have to see if we can find him at the next meeting, and get him to post his technique if he's willing -
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  #35  
Old 04-25-2017, 02:25 AM
dlowry dlowry is offline
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I pore-filled my last guitar with medium viscosity CA without any real drama. I wore the same vapour mask I use in the spray-booth. My previous pore-fillers were all tinted, and I wanted a clear filler.

I contacted Chuck Moore of Moore Bettah Ukeleles, who's been pore-filling his ukes with CA for many years, and he kindly sent me a description of his method - I believe he provides it freely to anyone who asks nicely...

The main points are:

1. Use a medium viscosity CA. He recommends Starbond EM150.
2. A little goes a VERY long way - don't slap on pints of the stuff.
3. Wipe on with folded paper towels. Prepare several in advance and change when the CA starts to harden on the paper.
4. Work out an application pattern - especially important for the sides, and work fast. Best to practice on scrap a few times.
5. Level-sand, leaving a film over the surface, don't go back to bare wood - might need a couple of coats, sanding back after each. It sands back pretty easily, although I've never tried epoxy for comparison.

The main skill is getting it spread and worked into the pores before it starts to go off - I think one benefit of the Starbond is that it has a longer open time. I couldn't gget it in Europe so used my normal workshop medium CA, and found speed was really of the essence with it. I'd also recommend to mask off the top as you would if refinishing just back and sides, to prevent CA getting onto the spruce - the medium stuff won't wick in under the tape.

I was very pleased with the results, and plan to use it from now on. Beau Hannam posted a helpful video where he uses Chuck's method to pore-fill a ukelele.

https://www.youtube.com/watch?v=bkGrEeHt96o

regards,
Drew

Last edited by dlowry; 04-25-2017 at 02:31 AM.
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  #36  
Old 04-25-2017, 12:08 PM
SnowManSnow SnowManSnow is offline
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I've also seen videos with people using medium 2p-10.

I have done a test scrap with both the ca for and a few coats of seal lac .

After sanding it down between coats and using the seal it's pretty dang slick.


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  #37  
Old 04-25-2017, 12:48 PM
M Hayden M Hayden is offline
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This is where being a hobbyist is fun. I do pore-filling using pumice/rottenstone and shellac. It's far too slow for production work but it produces a beautiful surface, albeit at the expense of a lot of time and work.

I've done CA filling once, when I just couldn't get the pores to fill on some padauk with enormous, drive-a-truck-through-them pores. I used a rubber spatula and did not leave much on the surface, and sanded back. A lot of it soaked through to the inside; the guitar's interior is blotchy because of it. But it did work where pumice and shellac were just too labor-intensive.
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  #38  
Old 04-25-2017, 01:16 PM
charles Tauber charles Tauber is online now
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Quote:
Originally Posted by M Hayden View Post
I do pore-filling using pumice/rottenstone and shellac.... on some padauk with enormous, drive-a-truck-through-them pores.... But it did work where pumice and shellac were just too labor-intensive.
I'm nearly finished pore filling a padauk back, sides and neck using pumice and shellac (Royal Lac). It is slow. Lots of pore to fill.
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  #39  
Old 04-25-2017, 01:35 PM
redir redir is offline
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I started using egg whites a while back. The first time I used it was just to fit in the motif of building a local woods guitar and as organic in nature as possible. Finished with nothing but bug poop and egg whites. It worked so well that I am sticking with it. and people I sell guitars to like the story... so it goes.

But it really does work well.
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  #40  
Old 04-25-2017, 01:35 PM
M Hayden M Hayden is offline
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Which padauk? Andaman or African? I think mine was Andaman - bright reddish orange, sweet smell, and pores big enough to mistake for a soundhole...
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  #41  
Old 04-25-2017, 02:17 PM
JLS JLS is offline
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Brian Burns gave an NCAL show & tell some years ago, porefilling with low odor CA glue.
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  #42  
Old 04-27-2017, 05:01 PM
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Rodger Knox Rodger Knox is online now
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I've used the thin CA for pore fill several times. I usually have an older bottle that has lost some of the solvent, it doesn't dry as quickly, and works better than a fresh bottle. Put a fan behind you, pour out a little puddle, and spread it around with an old credit card. You do have to work quickly, and there is the potential for disaster, but it's worked for me.
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